main/server/dhcp/files/11-dhclient

#!/bin/bash
# run dhclient.d scripts in an emulated environment

PATH=/bin:/usr/bin:/sbin
SAVEDIR=/var/lib/dhclient
ETCDIR=/etc/dhcp
interface=$1

eval "$(
declare | LC_ALL=C grep '^DHCP4_[A-Z_]*=' | while read opt; do
    optname=${opt%%=*}
    optname=${optname,,}
    optname=new_${optname#dhcp4_}
    optvalue=${opt#*=}
    echo "$optname=$optvalue"
done
)"

[ -f /etc/sysconfig/network ] && . /etc/sysconfig/network

[ -f /etc/sysconfig/network-scripts/ifcfg-$interface ] && \
    . /etc/sysconfig/network-scripts/ifcfg-$interface

if [ -d $ETCDIR/dhclient.d ]; then
    for f in $ETCDIR/dhclient.d/*.sh; do
        if [ -x $f ]; then
            subsystem="${f%.sh}"
            subsystem="${subsystem##*/}"
            . ${f}
            if [ "$2" = "up" ]; then
                "${subsystem}_config"
            elif [ "$2" = "down" ]; then
                "${subsystem}_restore"
            fi
        fi
    done
fi